oracle日期格式

insert into Ecp_Chat_Message(CHATID,CONTENT,IMGURL,SENDUSERID,SENDTIME,RECEIVEUSERID,STATE,ISREAD)
values
(1,'asdfdf','aaaa','kehu4',to_date('2011-12-03 12:55:45.333333','yyyy-mm-dd hh24:mi:ss.ff'),'serviceid',1,0)      

報錯如下:

日期格式圖檔在轉換整個輸入字元串之前結束

insert into Ecp_Chat_Message(CHATID,CONTENT,IMGURL,SENDUSERID,SENDTIME,RECEIVEUSERID,STATE,ISREAD)
values
(1,'asdfdf','aaaa','kehu4',to_date('2011-12-03 12:55:45','yyyy-mm-dd hh24:mi:ss'),'serviceid',1,0)      

insert into Ecp_Chat_Message(CHATID,CONTENT,IMGURL,SENDUSERID,SENDTIME,RECEIVEUSERID,STATE,ISREAD)
values
(1,'asdfdf','aaaa','kehu4',to_timestamp('2011-12-03 12:55:45.333333','yyyy-mm-dd hh24:mi:ss.ff'),'serviceid',1,0)